A model-independent algorithm to derive Ca2+ fluxes underlying local cytosolic Ca2+ transients

Local intracellular Ca2+ signals result from Ca2+ flux into the cytosol through individual channels or clusters of channels. To gain a mechanistic understanding of these events we need to know the magnitude and spatial distribution of the underlying Ca2+ flux. However, this is difficult to infer fro...

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Detalles Bibliográficos
Autores: Ventura, A.C., Bruno, L., Demuro, A., Parker, I., Dawson, S.P.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2005
País:Argentina
Institución:Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales
Repositorio:Biblioteca Digital (UBA-FCEN)
Idioma:inglés
OAI Identifier:paperaa:paper_00063495_v88_n4_p2403_Ventura
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_00063495_v88_n4_p2403_Ventura
Access Level:acceso abierto
Palabra clave:adenosine triphosphatase (calcium)
calcium channel
calcium ion
voltage gated calcium channel
algorithm
article
calcium binding
calcium cell level
calcium current
calcium signaling
calcium transport
cytosol
diffusion
fluorescence
mathematical analysis
model
Descripción
Sumario:Local intracellular Ca2+ signals result from Ca2+ flux into the cytosol through individual channels or clusters of channels. To gain a mechanistic understanding of these events we need to know the magnitude and spatial distribution of the underlying Ca2+ flux. However, this is difficult to infer from fluorescence Ca2+ images because the distribution of Ca2+-bound dye is affected by poorly characterized processes including diffusion of Ca2+ ions, their binding to mobile and immobile buffers, and sequestration by Ca2+ pumps. Several methods have previously been proposed to derive Ca2+ flux from fluorescence images, but all require explicit knowledge or assumptions regarding these processes. We now present a novel algorithm that requires few assumptions and is largely model-independent. By testing the algorithm with both numerically generated image data and experimental images of sparklets resulting from Ca2+ flux through individual voltage-gated channels, we show that it satisfactorily reconstructs the magnitude and time course of the underlying Ca2+ currents. © 2005 by the Biophysical Society.